This will be interesting.

1.  West was a better defender than Williams.

2.  Other than "Z", J. Smith was the Cavs only big man that could shoot.

3. "Z" and Big Ben are getting old.  "Z" at this point is basically immobile

4. Williams should improve the Cav's offense against the weaker defending teams in the league

Bottom line is that the Cav's front line at the #4 and #5 is too old and not very deep at all.  I don't think that when you take into account the aging of "Z" and Big Ben along with the departure of Smith their best shooting big man that the addition of Williams a less than average perimeter defender will be enough for the Cavs to get into the top bracket come playoff time, even with Lebron.